Extraordinary claims. Ordinary investigations.

Starting from a punctual object (O1), completely in focus, the light rays, after going through the lens, will pass through the center (O3) of the diaphragm and then through the second lens, ending in the photographic film in a point (F1), completely in focus.

On the other hand, starting from a punctual object (O2), completely out of focus, the light rays, after going through the lens, would converge at the point O4, but some of the light rays will be blocked by the diaphragm. Only part of it will pass through.

This part is, in fact, a cone with thousands of rays of light. Between points O3 and O4 we have what is called the circle of minimum confusion. As only light will pass, out of focus, through the diaphragm, and it blocks part of the light rays, then the physical shape of the diaphram is imprinted to the photographic film.

Spherical Aberration

It occurs when the objective lens is incapable of focusing the outer and axial rays in the same point. Because of the lens curvature, the borders are thinner while the center is thicker. If the lens is hit by parallel rays, they will pass through different thicknesses in the lens, and will therefore form many different focus points.

An objective lens with spherical aberration will form a diffuse image with little contrast in all visual field. We can reduce the problem closing the diaphragm, using only the central region of the lens.

An objective lens is composed of many elements, going from 7 up to 15 lenses, depending on its quality. This is all to eliminate or reduce the aberrations.

In the image below, we can see that a light was cut out of the original photo, to the right. It generated a coma reflection, to the left (notice the symmetry). Around the reflection we also see a good example of spherical aberration, forming a big ring.

This effect is very common on night films seen on the movies or TV, when car headlights are filmed coming towards the camera. It’s also very clear with TV studio light spots.

Out of focus

Something very similar happens with unfocused images. If we have the focus on a person, for instance, and in the background we have one or more lights, those will be out of focus, and reach the camera on that circle of minimum confusion.

This will imprint the image of the diaphragm on the photo. If we have a diaphragm with five parts, as in the example above, then the unfocused images will have that shape: a pentagon. If the diaphragm has six parts, as in the example below, we will have hexagons. And so on.

The same thing happens if you photograph a light source very closely, with the focus set to infinite. IN the example above, the small holes were captured in film as hexagons, as the diaphragm of the camera had six parts. At left, it’s also possible to see a reddish spherical aberration.

In this photo we can see that it’s out of focus, since the hexagons are all parallel to each other. If they were on a curve, they would align toward a common point.

Coma

The coma aberration happens when an objective lens is incapable of forming a puncutal oblique image, producing instead an asymmetrical light area. The light rays are reflected by the internal lenses and reach the film.

This aberration is the one most often confused with UFOs. See the example above of a photo that was cropped. In the uncropped photo, there will always be a symmetry of the source and the reflection in relation to the center of the photograph.

It’s always important to analyze the negatives to verify if the photograph wasn’t developed with cropping. See some examples below.

Cropped

Uncropped

Symmetry highlighted

Out of the visual field

Another interesting visual effect mistaken with UFOs occurs when the source of the light lies outside the visual field of the camera, but insed the visual field of the first lens (the outermost lens).

Those are usually taken almost against the Sun. This effect can be avoided by using a shade. See two examples below:

If you read and understood this article, you will probably start to look at UFO photos with a different view. You may also watch TV in a different way, noticing the many squares, pentagons, hexagons and polygons in general that appear all the time, as well as the Coma and spherical aberrations.

– By Claudeir Covo, ufologist and president of the Brazilian National Institute of Aerospatial Phenomena Investigation – INFA
And Paola Lucherini Covo, ufologist and secretary of INFA

Translated with their kind permission

CAELESTIA was initiated in 1994. Its purpose: to collect, investigate and document reports of unidentified aerial phenomena. The name CAELESTIA is borrowed from Latin and can best be translated as “affairs of the heavens”. The general idea behind the initiative was – and still is – that reports of “Unidentified Flying Objects” deserve a more correct treatment, be it from the scientific community or from the UFO community itself.

Special notice to the superb picture galleries, with an extensive list of objects and phenomena that can be mistaken for UFOs. The resarch & discussion also has some nice work, including an evaluation of the Belgian UFO wave, as as the case examples.

[via Vicente-Juan Ballester Olmos]

Location: Pirinopolis, Goias, Brazil
Date: February 2005

Regina Sylvia sent us this series of three amazing photos that she described as “UFOs disguised as clouds“. We suggested to her that they could have been just clouds, and she told us that:
“This ‘cloud’ was something strange… If it was just a cloud… I don’t know, but on this day we were going to the Pirineus (in Pirinopolis, Goias), and as we stopped at the city we saw this first cloud. Huge, amazing. Afterwards on our house, around two hours later, we saw the same cloud, huge, but it wasn’t just one, as there was another, smaller, a little to the left. The night came and… another cloud appeared in the same place, lit as if the Moon was behind it.”

At first sight, we thought these were just common lenticular clouds, as we told Regina. These clouds are formed with strong, vertical winds on irregular terrain. They also resemble “mountain cap” clouds, formed over the top of mountains.

But the images are not like the common lenticular clouds — as noted by Andreia Tschiedel, who remarked that these clouds are joined closely by other types of clouds. The first image shows a cumulus clouds along with the intriguing semi-spherical, translucent cloud. Were they UFOs disguising as clouds? Well, we Googled some more, and found a possible prosaic explanation.

They are Pileus clouds. “Pileus caps are made of ice crystals high in the troposphere. They form as a slab of air is shoved upward, in the shape of a dome or cap, just above a rapidly rising convective tower. Moisture in the dome condenses directly into an ice fog as the air rises and cools, forming the pileus. Next, the convection shoots right through the pileus layer. The lifted layer above the convective tower can’t be too dry (must have high humidity), or the pileus cap won’t develop.”

As images may be worth more than words, we present the image of the month for May 2005 of the Cloud Appreciation Society, taken by Justin Moore:

(source: CAS Cloud of the Month, May 2005)

With thanks to Regina Sylvia for the beautiful images.

Location: Viborg, Jutland, Denmark
Date: November 17, 1974

It all happened on a Sunday morning, when Mr. Laursen went on a walk with his dog. He liked taking photos of birds near the lake, and took his color 35mm camera with him. Then, he suddenly saw an enormous object in the air, got his camera and managed to take a shot. The captured image, in Kodacolor film, would be one of the most curious physical evidence of UFOs.
In 1979 the case was publicized on UFO-Kontakt magazine, where an analysis declared the object a “typical” alien spaceship encircled by a cloud. Many other publications around the world would go further claim that the flying saucer was camouflaging itself as a cloud, probably because there were “key NATO bases” in the area.

Comments: In 1993, artist Ned Kahn, who has among his interactive creations a three meter high mini-tornado in the World Financial Center in New York, created “Cloud Rings”, which you can see at right. A strange fog cloud is expelled from the central hole of a drum. A quick look at it may cause an instant dejá vù.

Kahn’s cloud ring is a stable toroidal vortex. They are better known as “smoke rings” created by smokers throughout history.

Both in its discoidal, seemingly solid upper form, as in its more loose lower appearance, Kahn’s vortex is an exact reproduction of the UFO photographed on that cold morning in 1974. The only difference is the scale, which suggests that the danish UFO was created by a very big sort of “drum”.

Ole Henningsen, of SUFOI (Scandinavian UFO Information), actually investigated this case, interviewing the main witness, and locating the exact place and direction in which the photo was taken. And he discovered that the photo almost captured the Houlkærvænget heating center, which is directly below the UFO-cloud photographed. The sight of these curious smoke clouds were not very uncommon when the boilers were being cleaned.

The Viborg UFO photo is therefore explained, and has little to do with NATO installations or alien spaceships camouflaging themselves as clouds.

This UFO didn’t turn into vapor. It already was.

See: Os OVNIs de Vórtice (in Portuguese) for more details.

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